Prior art of possible relevance includes the following U.S. Pat. Nos. 3,948,270 issued Apr. 6, 1976 to Hasson; 3,965,909 issued June 29, 1976 to Waddell et al; 3,978,863 issued Sept. 7, 1976 to Fettel et al; 4,029,104 issued June 14, 1977 to Kerber; 4,057,065 issued Nov. 8, 1977 to Thow; and 4,089,337 issued May 16, 1978 to Kronner et al; of which patents 3,948,270 and 4,089,337 are believed to be the most pertinent.
In my above identified patent there is disclosed a novel uterine cannula which is useful in a variety of gynecological procedures wherein uterine elevation or manipulation and/or uterotubal injection are indicated. Reference may be had to my patent for a specific identification of the nature and types of such procedures.
Considerable experience with the uterine cannula described in my prior patent illustrates that the same works extremely well for its intended purposes, suffering only minor inconveniences. For example, the rigid injection receiver therein disclosed and the nature of the handle utilized in the device are such that leakage is occasionally encountered. It is also desirable to provide a more positive cushioning of the cannula tip. Occasionally, due to the rigid nature of the injection receiver, when coupled to the tip of a syringe, relative motion between the two during use can cause breakage of the syringe tip.
Finally, the number of parts employed in my patented construction increases the cost of its manufacture.
The present invention is an improvement of my previously patented uterine cannula and intended to overcome one or more of the above problems.